1. Field of the Invention
The present invention is directed to an apparatus for conducting chemical reactions. More specifically, the present invention is directed to an apparatus which provides contact between a first gaseous reactant, a second gaseous reactant and a liquid reaction medium without intimate contact between the two gaseous reactants.
2. Background of the Prior Art
Many apparatus have been developed to permit gas-liquid contact. These apparatus are generally utilized in mass transfer operations between a gas and a liquid or to effectuate a chemical reaction between a gas and a liquid.
Oftentimes these gas-liquid contact type apparatus utilize a loop design. In such designs the principal means for providing fluid motion about the loop is bulk fluid density variations caused by the introduction of the gas into the liquid. Typically, in these loop-type gas-liquid contact apparatus, design variations usually involve the means by which the gas and liquid phases are separated after mass transfer, chemical reaction or the like has taken place.
Many such gas-liquid contact apparatus are known in the art. For example, U.S. Pat. No. 3,487,621 discloses a gas-liquid contact apparatus, which may include a solid material in suspension, which permits contact between gas and liquid without the assistance of any rotating part. This design allows only for a single gas to contact a single liquid.
U.S. Pat. No. 3,957,442 provides an apparatus for the production of glycerol dichlorohydrin. The design of this apparatus involves the introduction of two dissimilar gases into an aqueous liquid stream. However, the two gases, chlorine and allyl chloride, in effect, react with each other. Thus, while the apparatus of the '442 patent involves the use of two dissimilar gases, it does not provide means for keeping the gases from reacting with each other.
U.S. Pat. No. 4,342,876 is directed to an induced circulation reactor which permits the oxidation of p-xylene and p-methyltoluate with air in the presence of a catalyst to produce p-toluic acid and monomethylterephthalate. Although the design of this apparatus represents a classical "loop" reactor, only one gas is involved in the reaction scheme, an oxygen-containing gas, preferably air. The air causes circulation of the reaction medium through the loop by reducing the bulk density of the liquid reaction medium in the first column of the two vertical column loop reactor.
A particular problem associated with chemical reactions involving mixed multiple gaseous reactants such as oxygen and organic compounds is the need to insure that the concentration of each gas is within specified safety limits, i.e., outside the explosive zone, depending on the organic compound employed. Any attempt to operate inside the explosive zone can lead to a violent explosion. Generally, operation outside safety limits can also lead to undesirable side reactions.
Since oxygen and organic compounds are extensively employed together as feed stocks in numerous industrially important processes, it is apparent that new apparatus need be developed to allow such processes to be carried out more efficiently and with greater safety than in the past.
The above remarks establish the need in the art for a reactor system which permits contact between two gaseous reactants and a liquid reaction medium but which prevents intimate contact between the two gaseous reactants.